[4] The ICTV was formed from and is governed by the Virology Division of the International Union of Microbiological Societies.

Each subcommittee head, in turn, appoints numerous 'study groups', which each consist of one chair and a variable number of members dedicated to the taxonomy of a specific taxon, such as an order or family.

[2] In 2017, the ICTV endorsed a proposal to adapt the classification of viruses in order to keep up better with the growth of available sequences.

However, newly designated serial numbers, letters or combinations thereof are not acceptable alone as species epithets.

[10] A virus genus is a group of related species that share some significant properties and often only differ in host range and virulence.

[13] Acknowledging the importance of viral metagenomics, the ICTV recognizes that genomes assembled from metagenomic data represent actual viruses and encourages their official classification following the same procedures as those used for viruses isolated and characterized using classical virology approaches.

The 2018 and onward taxonomy is available online,[21] including a downloadable Excel spreadsheet of all recognized species.

It uses the Description Language for Taxonomy (DELTA) system, a world standard for taxonomic data exchange, developed at Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO).

DELTA is able to store a wide diversity of data and translate it into a language suitable for traditional reports and web publication.

For example, ICTVdB does not itself contain genomic sequence information but can convert DELTA data into NEXUS format.

[23] It can also handle large data inputs and is suited to compiling long lists of virus properties, text comments, and images.

ICTVdB has grown in concept and capability to become a major reference resource and research tool; in 1999 it was receiving over 30,000 combined online hits per day from its main site at the Australian National University, and two mirror sites based in the UK and United States.

The ICTV has begun discussions on how best to fix these problems, but decided that the time frame for updates and error correction were sufficiently long that it was best to take the site down rather than perpetuate the release of inaccurate information.